WELDTECH WT200MP - Gas Metal Arc Welding (GMAW); GMAW Process Overview and Applications; Flux Cored Arc Welding (FCAW); FCAW Process Overview and Shielding

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WT200MP Welding Machine
www.weldtech.net.nz
Gas Metal ARC Welding (GMAW).
Thisprocess,alsoknownasMIGwelding,CO2weld-
ing,MicroWireWelding,shortarcwelding,diptrans-
fer welding, wire welding etc., is an electric arc weld-
ing process which fuses together the parts to be
welded by heating them with an arc between a solid
continuous, consumable electrode and the work.
Shielding is obtained from an externally supplied
welding grade shielding gas. The process is normally
applied semi automatically; however the process
may be operated automatically and can be machine
operated. The process can be used to weld thin and
fairly thick steels, and some non-ferrous metals in all
positions.
GMAW Process
(Fig 1-1)
ShieldingGas
MoltenWeldMetal
Nozzle
Electrode Arc
BaseMetal
SolidiedWeldMetal
Flux Cored Arc Welding (FCAW)
This is an electric arc welding process which fuses to-
gether the parts to be welded by heating them with
an arc between a continuous ux lled electrode
wireandthework.Shieldingisobtainedthroughde-
composition of the ux within the tubular wire. Ad-
ditional shielding may or may not be obtained from
an externally supplied gas or gas mixture. The pro-
cess is normally applied semi automatically; however
the process may be applied automatically or by ma-
chine.
It is commonly used to weld large diameter elec-
trodes in the at and horizontal position and small
electrode diameters in all positions. The process is
used to a lesser degree for welding stainless steel
and for overlay work.
FCAW Process
(Fig 1-2)
Nozzle
(Optional)
FluxCored
Electrode
Arc
Base
Metal
Solidied
WeldMetal
Slag
Molten
Slag
MoltenMetal
ShieldingGas
(Optional)
Push
Vertical Drag Pull
Position of MIG Torch
(Fig 1-3)
TheangleofMIGtorchtotheweldhasaneecton
the width of the weld.
The welding gun should be held at an angle to the
weldjoint.(SeeSecondaryAdjustmentVariablesbe-
low).
Holdthegunsothattheweldingseamisviewedat
all times. Always wear the welding helmet with prop-
er lter lenses and use the proper safety equipment.
CAUTION!
Do not pull the welding gun back when the arc is
established. This will create excessive wire exten-
sion (stick-out) and make a very poor weld.
The electrode wire is not energized until the gun
trigger switch is depressed. The wire may therefore
be placed on the seam or joint prior to lowering the
helmet.
(Fig 1-4)
5
o
to15
o
LongitudinalAngle
Direction of Travel
90
o
Transverse
Angle
(Fig 1-5)
5
o
to15
o
LongitudinalAngle
30
o
to 60
o
Transverse
Angle
Direction
of Travel